某密闭容器中有X、氧气和二氧化碳三种物质，在一定条件下充分反应，测得反应前后各物质的质量如表．根据表中信息，判断下列说法正确的是（　　）

阅读短文，判断下列句子与短文内容是否相符。

    I lived in a village ten years ago．There were no buildings．There were no cars．There was a small school near my village．I went to school on foot．People couldn't use the Internet．We often climbed mountains and went fishing．Now there are many new buildings．There is a new school near the village．Children go to school by bus．People often play computer games at home．

“没有比青春的丧失同样重大的损失了。”这句话启示我们（    ）

下列句子中，加线词语使用正确的一项是（  ）